ZDI-10-098: Apple Webkit First-Letter Pseudo-Element Style Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-098
June 8, 2010
-- CVE ID:
CVE-2010-1401
-- Affected Vendors:
Apple
-- Affected Products:
Apple WebKit
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TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 9871.
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-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Apple's Webkit. User interaction is required
in that a user must visit a website or open a malicious document.
The specific flaw exists within the way Webkit implements the
'first-letter' css style. If a container with the first-color style has
it's contents replaced with a particular element, the library will
create a dual reference of the style in order to apply to its contents.
Later when the element is freed, the dangling reference will still be
applied to the style. Upon navigating the document's styles for either
repainting or style recalculation, the application will access the freed
memory which can lead to code execution under the context of the
application.
-- Vendor Response:
Apple has issued an update to correct this vulnerability. More
details can be found at:
http://support.apple.com/kb/HT4196
-- Disclosure Timeline:
2010-02-23 - Vulnerability reported to vendor
2010-06-08 - Coordinated public release of advisory
-- Credit:
This vulnerability was discovered by:
* wushi of team509
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